1. Field of the Invention
The present invention relates to a technique stereoscopic image display applicable to stereoscopic television sets, stereoscopic video recorders/players, stereoscopic videotelephones for effective communications at remote locations, and the like.
2. Description of Prior Art
Conventional techniques of displaying a stereoscopic image (three-dimensional image) include a glass scheme using specific glasses, and using a lenticular lens sheet. In the case of glasses a stereoscopic image is displayed and polarized glasses, liquid-crystal glasses, or an anaglyph scheme are used. A disadvantage of this system is the need for the viewer to wear glasses. This is particularly the case since the parties will be seen wearing glasses which may not be normal.
On the other hand, the technique of displaying a stereoscopic image using a lenticular lens sheet can be of direct viewing type wherein the lenticular lens sheet is arranged on the surface of a display such as a CRT, a liquid-crystal display, or the like, or at projection type in which an image is projected on a lenticular lens sheet using a projector.
With the lenticular lens sheet scheme, a viewer can watch a stereoscopic image without wearing glasses. However, in order to assure stereoscopic viewing over a wide field, a large number of images projected from 6 to 8 places are required, and the arrangement of the apparatus becomes complicated and expensive. To realize such stereoscopic viewing by images projected from two places, a technique is known for mechanically tracking the head of the viewer (e.g., Alfred Schwartz; "Head Tracking Display" IEEE Trans. ED-33, 8 (Aug, 1986)). However, a tracking speed is limited due to its mechanical operation.